====== Beer's Law ======
Beer-Lambert's law is the relationship between absorbance, concentration, and path length.

$A = εbc$

===== Variables =====
  * $A =$ absorbance
  * $ε =$ molar absorptivity (M^-1cm^-1)
  * $b =$ path length (cm)
  * $c =$ concentration (M)

===== Intuition =====
  * The higher the concentration, the higher the absorbance.
  * The longer the path length, the higher the absorbance.